Operations management highly contributes to the success of companies. Effective operations management gives the potential to increase revenues and at the same time reduce costs of production. It may also reduce the amount of investment needed. What are the basic operational control rules to manage inventory and resources? Based on quantitative analysis you can acquire a deeper insight into relationships between resource utilization, throughput time, inventory investments and operational customer service. These qualitative insights enable to understanding of the principles behind widely promoted concepts such as Lean and Six Sigma.